赤水河流域生态水文过程对土地利用/覆被变化的响应

  目的  分析赤水河流域近十年土地利用变化特征，探索生态文明建设背景下水资源空间分配与水文循环过程，以期为流域提供合理的土地利用规划依据及促进流域的可持续发展。  方法  以赤水河流域为研究对象，在1967 ~ 2020年的气候背景下，基于SWAT（Soil and Water Assessment Tool）模拟了流域2008 ~ 2020年的地表径流、地下径流和总径流量，从而分析三者变化特征及其对土地利用/覆被变化的响应。  结果  研究表明:流域三个站点率定期和验证期的R2、NSE均大于0.6，构建的SWAT模型适合赤水河流域水文过程的模拟；流域以耕地、林地和草地为主，研究期间耕地、林地、草地面积分别减少了47.57 km2、23.51 km2、4.75 km2，水域、建设用地面积分别增加了9.42 km2、65.98 km2；4期土地利用背景下，地表径流和总径流量呈波动上升趋势，地下径流呈波动下降趋势，且与地下径流相比，地表径流对土地利用/覆被变化更敏感；对地表径流而言，建设用地 > 耕地 > 林地 > 草地，地下径流则是林地 > 草地 > 耕地 > 建设用地，而总径流量表现为耕地 > 建设用地 > 林地 > 草地。  结论  总体上截流蓄水效果表现为林地 > 草地 > 耕地 > 建设用地，林草地具有较好的截流蓄水功能。

Responses of Ecohydrological Processes to Land Use/Cover Change in the Chishui River Basin

  Objective  In order to provide a reasonable basis for land use planning and promote the sustainable development of the basin, the characteristics of land use change in Chishui River Basin had been analyzed in recent ten years, in order to explore the spatial allocation of water resources and hydrological cycle process under the background of ecological civilization construction.  Method  Under the climate background of 1967-2020, based on the SWAT (Soil and Water Assessment Tool) model, the surface runoff, underground runoff and total runoff of the Chishui River Basin were simulated from 2008 to 2020, thereby the variation characteristics and responses to land use/cover change of them were analyzed.  Result  The results showed that (1) the R2 and NSE of the three stations were greater than 0.6, and the SWAT model was suitable for the hydrological process simulation of Chishui River Basin; (2) The basin was dominated by cultivated land, forest land and grassland. During the study period, the area of cultivated land, forest land and grassland decreased by 47.57 km2, 23.51 km2 and 4.75 km2, respectively. While the area of water area and construction land increased by 9.42 km2 and 65.98 km2, respectively; (3) Under the background of 4 stage land uses, the surface runoff and total runoff showed a fluctuating upward trend, while the underground runoff showed a fluctuating downward trend, and the surface runoff was more sensitive to land use / cover change than the underground runoff; (4) The surface runoff order was construction land > cultivated land > forest land > grassland, while the underground runoff order was forest land > grassland > cultivated land > construction land, and the total runoff order was cultivated land > construction land > forest land > grassland.  Conclusion  On the whole, the effect of river closure and water storage was forest land > grassland > cultivated land > construction land, and forest grassland had better function of river closure and water storage.